GWD11数学部分第3、10、29题

yuyanhan

Q3:

A certain company assigns employees to offices in such a way that some of the offices can be empty and more than one employee can be assigned to an office. In how many ways can the company assign 3 employees to 2 different offices?

A. 5

B. 6

C. 7

D. 8

E. 9

Answer: d为何我分不出8种呢，请指教

Q10:

A certain quantity数量 is measured on two different scales,按比例绘制 the R-scale and the S-scale, that are related linearly. Measurements on the R-scale of 6 and 24 correspond to measurements on the S-scale of 30 and 60, respectively. What measurement on the R-scale corresponds to a measurement of 100 on the S-scale?

A. 20

B. 36

C. 48

D. 60

E. 84

Answer: c，不是36吗，这怎么做呢

Q29:

For any integer k greater than 1, the symbol k* denotes the product of all the fractions of the form , where t is an integer between 1 and k, inclusive. What is the value of ?

A. 5

B5/4.

C.4/5

D.1/4

E.1/5

Answer: e完全不明白，我是数学盲哎

sammen

3，有2个情况1）3个人再一个房间2种；2）2＋1个人模式，就是其中一个房间有2个人，6种。一共8种。

10象是个比例的东西，是线性方程

30=6a+b

60=24a+b

a=5/3,,b=20

所以方程式 y=5/3X+20..代入

100=5/3X+20-->5/3X=80---->X=48

29 symbol k* denotes the product of all the fractions of the form，如5*=1/5*1/4*1/3*1/2*1/1

故5*/4*=（1/5*1/4*1/3*1/2*1/1）/(1/4*1/3*1/2*1/1)=1/5